class Animal:
    def talk(self):
        pass


class Cat(Animal):
    def talk(self):
        print("喵喵")


class Dog(Animal):
    def talk(self):
        print("旺旺")

# 多继承 Mixins 使用
class UseToolMixin:
    def use_tool(self):
        print("使用工具")


class People(UseToolMixin,Animal):
    def talk(self):
        print("人语")


p = People()
p.use_tool()
p.talk()
